Standpipe distributor for short time contact of hydrocarbon compounds with particles

Abstract

An arrangement for the controlled production of an essentially linear array of hydrocarbon feed injection jets reduces required clearances and elevation while facilitating modification of the contacting locating a feed distributor containing a linear array of jets at a standpipe junction point to provide choke point for particle flow control. The flow properties of the extended particle layer are controlled by adjusting the density of the particles above the choke point created by the upper part of the standpipe inside diameter and the top of the distributor. Steam or another fluidization medium may be added to the particles directly above the distributor for this purpose. This invention can also modify the particle or feed injection characteristics by changing the projection of the distributor into the standpipe to adjust the flow area over the choke point and by the use of bottom slides or baffles to change the flow area size and configuration. Location of the distributor at a standpipe junction will also typically allow the placement of the distributor at a lower location in the process which eliminates the need to add vessel height for supplying pressure drop for the particle discharge point. The distributor arrangement also fits compactly into most common standpipe junctions. Thus, the arrangement of this invention solves the problem of inserting an extended array of feed injection points into a fluidized particle contacting process without providing a large amount of clearance or additional vessel height.

We claim: 
     
       1. An apparatus for injecting a plurality of uniform jets into an extended dispersion of moving particles within a confined conduit, apparatus comprising: a particle and gas separator;   a conduit for carrying a mixture of particles and gas to the separator having at least one sloped portion;   a flow restriction located in the conduit upstream from the separator and partially occluding the top or bottom of the conduit having configuration to create a horizontally extended layer of particles flowing through the conduit; and,   a feed injector located downstream of the flow restriction and upstream of the separator for creating a horizontally extended jet of feed and positioned to inject the jet of feed substantially transversely into the flowing layer of particles.   
     
     
       2. The apparatus of claim 1 wherein a gas tap communicates with a portion of said conduit upstream of said flow restriction for adding gas therein. 
     
     
       3. The apparatus of claim 1 wherein a flat baffle is located in the conduit downstream of the flow restriction. 
     
     
       4. The apparatus of claim 1 wherein the distance along the conduit from the feed injector to the separator does not exceed the inside diameter of the conduit. 
     
     
       5. The apparatus of claim 1 wherein a distributor provides the feed injector and the flow restriction. 
     
     
       6. The apparatus of claim 1 wherein the open area of the conduit at the flow restriction is reduced to a range of from 50 to 80% of the open area of the conduit immediately upstream or downstream of the flow restriction. 
     
     
       7. An apparatus for injecting a plurality of uniform jets into an extended dispersion of moving particles within a confined conduit, apparatus comprising: a particle and gas separator;   a conduit for carrying a mixture of particles and gas to the separator having a junction point where the slope of the conduit decreases downstream of the junction such that the axis of the conduit upstream of the junction makes an angle of from 30 to 90 degrees with the horizontal and axis of the conduit downstream of the junction makes and angle of 0 to 45 degrees with the horizontal; and,   a distributor defining an upper surface below the junction point that defines a flow restriction between the junction point and the upper surface that partially occluding the bottom of the conduit, the upper surface having a configuration to create a horizontally extended layer of particles flowing over the distributor and transversely to the face of the distributor and defining at least one opening for injecting a horizontally extended jet of feed across the face of the distributor.   
     
     
       8. The apparatus of claim 7 wherein a gas tap communicates with a portion of conduit upstream of the distributor for adding gas therein. 
     
     
       9. The apparatus of claim 7 wherein a flat baffle is located in the conduit downstream of the distributor. 
     
     
       10. The apparatus of claim 1 wherein the open area of the conduit at the flow distributor is reduced to a range of from 50 to 80% of the open area of the conduit immediately upstream or downstream of the flow distributor. 
     
     
       11. An apparatus for injecting a plurality of uniform jets into an extended dispersion of moving particles within a confined conduit, apparatus comprising: a particle and gas separator;   a sloped conduit having an angle of 30 to 60 degrees from the horizontal axis for carrying a mixture of particles and gas to the separator; and,   a distributor located in the top of the conduit upstream from the separator and partially occluding the top of the conduit having configuration to create a horizontally extended layer of particles flowing through the conduit and defining at least one opening for injecting a horizontally extended jet of feed downwardly into the flowing catalyst layer.   
     
     
       12. The apparatus of claim 11 wherein a gas tap communicates with a portion of conduit upstream of the distributor for adding gas therein.